Walter Conrad Arensberg (1878, Pittsburgh - Pennsylvania, 1954) was an American art collector, critic and poet. His father was part owner and president of a crucible steel company. He majored in English and philosophy at Harvard University. With his wife Louise (1879-1953), he collected art and supported artistic endeavors.

Arensberg's work The cryptography of Shakespeare (1922) claims to find acrostics and anagrams in the published works of Shakespeare which reveal the name of Bacon. In The secret grave of Francis Bacon and his mother in the Lichfield chapter house (1923) and The Shakespearean mystery (1928) he used a "key cipher" to find further messages connected with the Rosicrucians.
Analysis by William Friedman and Elizebeth Friedman shows that none of the methods has cryptographic validity.

Several volumes of his Symbolist-influenced verse were also published, including 1914's Poems and 1916's Idols. His poem Voyage a l'Infini was anthologized by Edmund Clarence Stedman.